SMS marketing: what it is, how it works and campaign examples
How to use SMS to sell and keep your customers informed, with examples and legal requirements
SMS marketing is the use of text messages to send promotions, notices and reminders to customers who have given their permission to receive them. The message reaches the phone instantly, with no need for an internet connection or an app.
With an SMS sending service you can send the same campaign to thousands of numbers at once. This is known as mass SMS.
How does SMS marketing work?
An SMS campaign follows almost the same steps as an email campaign:
- You get permission. The customer agrees to receive your SMS through a form, in your store or when buying.
- You choose a platform. You import the numbers or use the ones in your contact list.
- You write the message. An SMS has 160 characters, or 70 if you use emojis or special characters. If you go over, it is sent as several SMS.
- You set your sender. Instead of a number, your company name can appear, from 3 to 11 characters.
- You send and measure. You schedule the send and check how many messages were delivered and how many clicks your link received.
Types of SMS marketing
Not all SMS have the same goal. These are the most common:
| Type | What it’s for | Example |
|---|---|---|
| Promotional | Sell with a specific offer | Weekend discount |
| Reminder | Reduce no-shows and forgotten appointments | Hair salon appointment tomorrow at 10:00 |
| Transactional | Report on an order or a request | Your order ships today |
| Reactivation | Win back customers who have stopped buying | We miss you: 15% off your next purchase |
| Survey | Find out what the customer thinks | Rate your visit from 1 to 5 |
SMS marketing examples to copy
Change the brand name and the link, and make sure it doesn’t go over 160 characters:
| Industry | Message |
|---|---|
| Fashion store | MODAMAR: 20% off the entire website, only until Sunday. Use the code FINDE20 at modamar.es/ofertas. To opt out, reply STOP |
| Clinic | CLINICASOL: a reminder of your appointment on Thursday the 9th at 17:30. If you can’t make it, call us on 910 000 000. |
| Restaurant | LACASONA: this Friday, tasting menu for €25. Book at lacasona.es/reserva. To opt out, reply STOP |
| Training school | FORMAPLUS: only 5 places left on the October Excel course. Sign up at formaplus.es/excel. Opt out: STOP |
| Ecommerce | TECNOSHOP: your order 4521 is on its way. Track it at tecnoshop.es/envio |
Launch your first SMS campaign
Send SMS from the same dashboard as your email marketing, with a custom sender and delivery statistics.
Is SMS marketing legal in Spain?
Yes, as long as you comply with the law. Two laws apply to sending advertising SMS in Spain:
- LSSI (Article 21). You need the recipient’s prior, express consent. The exception is your own customer, if you write to them about products similar to the ones they have already bought. Every message must offer a simple, free way to unsubscribe.
- GDPR. It regulates how you collect, store and use phone numbers. You must state what you use them for and be able to prove you have permission.
Before acquiring new contacts, also check the Robinson List, where people who don’t want to receive advertising sign up. Sending without permission is spam, by SMS too.
Advantages and limits of SMS marketing
SMS works very well for urgent messages, but it isn’t right for everything:
| Advantages | Limits |
|---|---|
| It arrives instantly and is read within minutes | Only 160 characters per message |
| It doesn’t need an internet connection or an app | Every SMS has a cost |
| Any phone can receive it | It doesn’t support images (that’s what MMS is for) |
| It’s easy to measure | If you overdo it, customers unsubscribe |
The key is to send sparingly and with a clear reason: an offer with a deadline, a reminder or a notice the customer is expecting.
SMS, email or WhatsApp: which to use
Each channel has its role. The best approach is to combine them:
| Channel | Best for | Limits |
|---|---|---|
| SMS | Urgent notices, reminders and flash sales | 160 characters and a cost per message |
| Newsletters, catalogs and long-form content | It can take longer to be read | |
| Conversations and customer service | The user must have the app and agree to receive messages |
For example, send the full promotion by email and, a few hours before it ends, an SMS reminder.
How much does SMS marketing cost?
You pay per message sent. With Mailrelay, an SMS to Spain costs between €0.0345 and €0.0357 depending on the package, excluding VAT:
| Package | Price | Price per SMS |
|---|---|---|
| 350 SMS | €12.50 | €0.0357 |
| 7,500 SMS | €260 | €0.0347 |
| 50,000 SMS | €1,725 | €0.0345 |
Credits last one year and there is no commitment. A long message counts as several SMS. The price varies by country: you can find it on the SMS pricing page.
How Mailrelay helps with your SMS marketing
With Mailrelay you send your SMS from the same dashboard as your email campaigns. You can paste a list of numbers or use the ones from your contacts.
The editor warns you if the message is too long and splits it automatically. You also choose the sender name and see in the statistics how many SMS were delivered.
Send SMS to your customers with Mailrelay
Packages from 350 SMS, no commitment, with support via chat, ticket and phone.
Frequently asked questions about SMS marketing
These are the most common questions before launching an SMS campaign.
What is an SMS campaign?
It’s a batch of text messages sent to a group of customers with a specific goal, such as selling, reminding them of an appointment or notifying them about an order.
How many characters does an SMS have?
160 characters with the standard alphabet and 70 if you include emojis or special characters. If the text is longer, it is split into several SMS and each one is charged.
Can you send advertising SMS without permission?
No. In Spain, the LSSI requires prior consent, unless the person is already your customer and you write to them about similar products. They must always be able to unsubscribe.